A device for laterally aligning sheets in sheet-processing machines includes a pulling device having a drivable transport roller and a dabber roller mounted on a pivotable lever. A spring system cooperates with the lever for adjusting a pressing force between the rollers. The spring system has a progressive spring characteristic.
|
14. A push/pull lay device, comprising:
a pulling device having a pivotable lever;
a drivable transport roller;
a dabber roller mounted on said pivotable lever; and
a spring system cooperating with said lever and adjusting a pressing force between said rollers, said spring system having a progressive spring characteristic;
said spring system having at least two helical compression springs disposed coaxially with respect to one another and connected in tandem.
1. A push/pull lay device, comprising:
a pulling device having a pivotable lever;
a drivable transport roller;
a dabber roller mounted on said pivotable lever; and
a spring system cooperating with said lever and adjusting a pressing force between said rollers, said spring system having a progressive spring characteristic;
said lever having a bearing axis and a point at which said spring system is applied to said lever, and at least one of said bearing axis and said spring application point being adjustable in location along said lever.
12. A sheet-fed printing machine, comprising:
a push/pull lay device including:
a pulling device having a pivotable lever;
a drivable transport roller;
a dabber roller mounted on said pivotable lever; and
a spring system cooperating with said lever and adjusting a pressing force between said rollers, said spring system having a progressive spring characteristic;
said lever having a bearing axis and a point at which said spring system is applied to said lever, and at least one of said bearing axis and said spring application point being adjustable in location along said lever.
13. In a sheet-fed printing machine having a lateral sheet alignment device, a push/pull lay, comprising:
a pulling device having a pivotable lever;
a drivable transport roller;
a dabber roller mounted on said pivotable lever; and
a spring system cooperating with said lever and adjusting a pressing force between said rollers, said spring system having a progressive spring characteristic;
said lever having a bearing axis and a point at which said spring system is applied to said lever, and at least one of said bearing axis and said spring application point being adjustable in location along said lever.
2. The sheet-aligning device according to
3. The sheet-aligning device according to
4. The sheet-aligning device according to
5. The sheet-aligning device according to
6. The sheet-aligning device according to
7. The sheet-aligning device according to
8. The sheet-aligning device according to
9. The sheet-aligning device according to
10. The sheet-aligning device according to
11. The sheet-aligning device according to
|
The invention relates to a device for laterally aligning sheets in sheet-processing machines, especially printing presses.
Lateral alignment of an infed sheet is usually performed by a pulling or pushing lay, which pulls or pushes the sheet against a stop. In this regard, a force is exerted on the sheet, which moves the sheet into a friction lock against the stop. The pull force or traction has to be adjusted in accordance with the speed, grammage and other settings, such as, vacuum or suction air applied to the suction belt. For printing materials with a low grammage, for example, a low pulling force is needed, and for printing materials with a high grammage, a high pulling force is needed. In addition, regions of lower grammages require a more precise setting of the pulling force than regions of high grammages.
A device of the type referred to at the introduction hereto has been disclosed in German Published, Non-Prosecuted Patent Application DE 30 11 626 A1. In that case, the pulling or pushing force is effected by two rollers which are set against one another and by which, in principle, cost-effective, exact lateral alignment of the sheet is made possible. In particular, in this regard, the sheet is pressed against a rotating roller by a freely rotatable roller, a so-called dabber roller. The required pressing force is applied by a tension or compression spring.
In the heretofore known reel-to-reel system according to the aforementioned German Published, Non-Prosecuted Patent Application DE 30 11 626 A1, the pulling force is adjusted via a spring and an adjusting screw. The spring is of the type having a linear characteristic. The adjustment is thereby equally precise over the entire range of the pulling force. If one would wish to increase the maximum possible pulling force within the existing installation space, this increase would be achieved at a cost of the adjustment accuracy.
Attempts have been made to vary the precision of the adjustment (note hereinabove), depending upon the respective requirements, by providing different compression springs, which the printer has to install in the pulling lay, depending upon the grammage. A disadvantage of such a solution for the problem is the great effort that must be made for installation or assembly purposes when the printing material has to be changed, and that material parts tend to lie around in the open in the vicinity of the feeder.
It is accordingly an object of the invention to provide a device for laterally aligning sheets in sheet-processing machines, especially printing presses, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and in which it is possible to adjust a pulling force in a relatively simple manner without additional installation or assembly work over the greatest possible region of printing material, so that adjustment accuracy should be high in regions that require only a comparatively low pulling force.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a device for laterally aligning sheets in sheet-processing machines, comprising a pulling device having a drivable transport roller and a dabber roller mounted on a pivotable lever. A spring system cooperates with the lever for adjusting a pressing force between the rollers. The spring system has a progressive spring characteristic.
In accordance with another feature of the invention, the lever has a bearing axis and has a point at which the spring system is applied to the lever. At least one of the bearing axis and the spring application point is adjustable in location along the lever.
In accordance with a further feature of the invention, the spring system serves for applying a force to the lever in a direction defined by an angle which is adjustable.
In accordance with an added feature of the invention, the spring system has a spring characteristic composed of a plurality of linear sections of varying slope.
In accordance with an additional feature of the invention, the spring system has a continuously progressive characteristic.
In accordance with yet another feature of the invention, the spring system further comprises at least two helical compression springs disposed coaxially with respect to one another and connected in tandem.
In accordance with yet a further feature of the invention, the at least two helical compression springs are of different hardness and, together with a guide pin extending therethrough, are disposed behind one another in a blind borehole provided in a sleeve part formed as an adjusting screw. A first one of the helical compression springs has a harder spring characteristic and serves for acting directly on the lever of the pulling device. A second one of the helical compression springs has a softer spring characteristic and adjoins the first helical compression spring at a rear end thereof.
In accordance with yet an added feature of the invention, the guide pin has a collar spatially separating the first and the second helical compression springs. The sheet-aligning device further includes a ledge formed in the adjusting screw in an upper part of the blind borehole. The ledge serves as a stop in cooperation with the collar.
In accordance with yet an additional feature of the invention, a first one of the helical compression springs is directly active on the lever and has a harder characteristic than a second one of the helical compression springs. The first spring carries a pot-like sleeve at a rear end of the first spring. The pot-like sleeve is formed with a radially outwardly directed rim by which the sleeve engages over the rear end of the first spring. The second spring is received in the pot-like sleeve and is braced against a rear end of an adjusting screw which is surrounded by the first and second helical compression springs in such a manner that the first and second helical compression springs are disposed concentrically with respect to one another.
In accordance with still another feature of the invention, the spring system further comprises at least two helical compression springs disposed coaxially with respect to one another and connected in parallel.
In accordance with still a further feature of the invention, the two springs, respectively, are a first helical compression spring with a harder characteristic, and a second helical compression spring with a softer characteristic disposed concentrically within the first helical compression spring. The two springs are directly actable on the lever. The first helical compression spring is braced against a rear surface of a stop fixed to a housing, and the second helical compression spring is braced against a rear surface of an adjusting screw surrounded by both the first and the second helical compression springs.
In accordance with still an added feature of the invention, the spring system is a conical helical compression spring having a diameter which increases towards the lever.
With the objects of the invention in view, there is also provided a sheet-fed printing machine, comprising a device for laterally aligning sheets, including a pulling device having a drivable transport roller and a dabber roller mounted on a pivotable lever. A spring system cooperates with the lever for adjusting a pressing force between the rollers. The spring system has a progressive spring characteristic.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a device for laterally aligning sheets in sheet-processing machines, especially printing presses, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now to the figures of the drawings in detail and first, particularly, to
The lever 13 is acted upon from above by a force applied by a spring system 16. As can also be seen in particular from the enlarged fragmentary and somewhat simplified view of
The overall characteristic of the spring system 17, 18 which results is illustrated in
With the aforedescribed in tandem-connected spring configuration, an overall characteristic is therefore realized in a simple way which permits more precise adjustment in the range of low pulling force and, at the same time, permits a high pulling force with a limited adjustment travel of the setting screw 20.
A different embodiment of an in tandem-connection of two compression springs, which is modified somewhat in comparison with the spring configuration according to
A further different embodiment according to
For the purpose of comparison with the spring characteristics 28, 35 and 36 having a progressive course overall, a further linear spring characteristic 42, corresponding to the prior state of the art for pulling devices, is represented in the plot diagram of FIG. 7. The aforedescribed advantages of the spring system according to the invention become particularly clear therefrom.
As is believed to be apparent from
In the position of the lever bearing axis 43 according to
In the configuration according to
The measures described hereinabove and revealed by
Additionally or alternatively, the measures apparent from FIGS. 12 and/or 13 can also be taken. In the alternative embodiment according to
Patent | Priority | Assignee | Title |
10005631, | Oct 24 2014 | Bobst Mex SA | Lateral positioning device for a sheet element |
7635128, | Dec 17 2003 | Ryobi Ltd. | Sheet positioning apparatus in a sheet feeding section of a printing press |
Patent | Priority | Assignee | Title |
DE3011626, | |||
DE837703, | |||
DE971251, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Aug 30 2002 | Heidelberger Druckmaschinen AG | (assignment on the face of the patent) | / | |||
Aug 30 2002 | GRASMUCK, GEORG | Heidelberger Druckmaschinen Aktiengesellschaft | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 013413 | /0183 |
Date | Maintenance Fee Events |
Sep 22 2008 | REM: Maintenance Fee Reminder Mailed. |
Mar 15 2009 | EXP: Patent Expired for Failure to Pay Maintenance Fees. |
Date | Maintenance Schedule |
Mar 15 2008 | 4 years fee payment window open |
Sep 15 2008 | 6 months grace period start (w surcharge) |
Mar 15 2009 | patent expiry (for year 4) |
Mar 15 2011 | 2 years to revive unintentionally abandoned end. (for year 4) |
Mar 15 2012 | 8 years fee payment window open |
Sep 15 2012 | 6 months grace period start (w surcharge) |
Mar 15 2013 | patent expiry (for year 8) |
Mar 15 2015 | 2 years to revive unintentionally abandoned end. (for year 8) |
Mar 15 2016 | 12 years fee payment window open |
Sep 15 2016 | 6 months grace period start (w surcharge) |
Mar 15 2017 | patent expiry (for year 12) |
Mar 15 2019 | 2 years to revive unintentionally abandoned end. (for year 12) |